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EGR vacuum test question

Discussion in '80-Series Tech' started by semlin, Feb 29, 2004.

  1. semlin

    semlin discouraged user

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    In my 94 FSM and Riley's 95 FSM there are 3 vacuum test diagnostic procedures for the EGR system. The last two direct you to connect lines to the intake manifold. WTF?? Is there a vacant vacuum port on the intake manifold I don't know about? Looked but can't see anything.

    The manuals also make it fairly unclear where to apply and/or measure the vacuum except for the first test. I think in the second test the vacuum gauge stays in the same place as this first, but in the third test I am not sure.

    If anyone speaks toyota mechanicese and can explain the last two tests in layperson's terms I will be in your eternal debt.

    thanks
    Semlin
     
  2. landtank

    landtank SILVER Star

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    What page are you guys on?
     
  3. semlin

    semlin discouraged user

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    sorry it's at home, while I'm here pretending to work. In the engine section under EGR just before the EGR disassembly section.
     
  4. landtank

    landtank SILVER Star

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    I did take a look. From what I see you are testing 3 parts of the system. The VSV, Modulator and EGR valve. Not sure what your asking for. Manifold vacuum should be at the VSV and should only pass when engine temp and rpms conditions are met. The modulator has similar conditions concerning rpms. And the EGR valve needs to operate properly when vacuum is applied. Sorry I can't be of more help.
     
  5. semlin

    semlin discouraged user

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    Rick, the problem is figuring how to hook up the hoses to run the vacuum tests. There is a reference to "intake manifold" that makes no sense.
     
  6. Beowulf

    Beowulf

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    Simon,

    I unplugged one of the same sized hoses on the intake and plugged into the nipple for manifold vacuum. I can't remember exactly which one but it was one that was the same size, right on top of the manifold, didn't cause any perceptible running problem with it removed, and I could feel the vacuum by putting my finger on the nipple.

    (edit...) I now remember going to Pep Boys and buying 3' of the same sized hose since I didn't have any spare hose that was long enough to do the test.

    I'll post a pic if needed.

    -B-